It's high stakes for UK firms as sports wagering starts to spread in America.

From Tuesday, new guidelines on betting entered into effect in Delaware, a tiny east coast state about two hours from Washington.

Neighbouring New Jersey could start accepting sports betting bets as early as Friday.

The changes are the first in what could become a wave of legalisation after the Supreme Court last month cleared the way for states to allow sports wagering.

The market sees a "as soon as in a generation" chance to establish a new market in sports-mad America, stated Dublin-based financial expert David Jennings, who heads leisure research at Davy.

For UK firms, which are facing debt consolidation, increased online competitors and tougher rules from UK regulators, the timing is especially opportune.

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But the industry states depending on the US remains a risky bet, as UK companies deal with complicated state-by-state guideline and competitors from established regional interests.

"It's something that we're actually concentrating on, however equally we don't wish to overhype it," said James Midmer, spokesman at Paddy Power Betfair, which just recently acquired the US fantasy sports betting website FanDuel.

'Take time'

The US represented about 23% of the world's $244bn (₤ 182bn) in video gaming profits in 2015, according to a report by Technavio, external released in January.

Firms are intending to take advantage of more of that activity after last month's choice, which struck down a 1992 federal law that barred states outside of Nevada and a few others from authorising sports betting.

The judgment found the law was an over-reach of federal power. But the court it did not in fact legalise sports betting wagering, leaving that concern to local lawmakers.

That is anticipated to lead to considerable variation in how companies get accredited, where sports betting can take place, and which events are open to speculation - with big ramifications for the size of the marketplace.

Potential revenue ranges from $4.2 bn to almost $20bn each year depending on factors like the number of states relocate to legalise, Oxford Economics approximated in a 2017 study for the American Gaming Association.

"There was a great deal of 'this is going to be big'", said Will Hawkley, London-based head of leisure for experts KPMG.

Now, he stated: "I believe the majority of individuals ... are taking a look at this as, 'it's a chance but it's not going to be $20bn and it's going to be state by state and it's going to require time'."

'Remains to be seen"

Chris Grove, handling director at Eilers & Krejcik Gaming, anticipates that 32 states will legalise sports betting wagering in some form by 2023, producing a market with about $6bn in yearly revenue.

But bookies deal with a far different landscape in America than they do in the UK, where betting shops are a frequent sight.

US laws limited betting largely to Native American lands and Nevada's Las Vegas strip up until reasonably recently.

In the popular creativity, sports betting has actually long been connected to a 1919 baseball World Series match-fixing scandal.

States have actually also been slow to legalise many kinds of online gaming, in spite of a 2011 Justice Department viewpoint that appeared to remove barriers.

While sports betting wagering is usually viewed in its own classification, "it plainly stays to be seen whether it gets the kind of momentum people think it will," said Keith Miller, law professor at Drake University and co-author of a book about sports wagering policy.

David Carruthers is the previous president of BetonSports, who was jailed in the US in 2006 for running an overseas online sportsbook and served jail time.

Now an expert, he states UK companies should approach the marketplace carefully, picking partners with caution and preventing mistakes that might lead to regulator reaction.

"This is a chance for the American sports betting gambler ... I'm uncertain whether it is a chance for business," he states. "It really is reliant on the outcome of [state] legislation and how business operators pursue the opportunity."

'It will be partnerships'

As legalisation starts, sports wagering companies are lobbying to fend off high tax rates, along with requests by US sports betting leagues, which wish to collect a percentage of earnings as an "integrity cost".

International companies face the included challenge of a powerful existing video gaming industry, with casino operators, state-run lotteries and Native American people that are seeking to safeguard their grass.

Analysts say UK companies will need to strike partnerships, using their knowledge and technology in order to make inroads.

They indicate SBTech's current announcement that it is offering technology for Kentucky Derby operator Churchill Downs as an example of the sort of offers most likely to materialise.

"It will be a win-win for everyone, however it will be partnerships and it will be driven by innovation," Mr Hawkley said.

'It will just depend'

Joe Asher, chief executive at William Hill US, is clear-eyed about the realities.

The company has been purchasing the US market because 2011, when it bought 3 US firms to develop an existence in Nevada.

William Hill now utilizes about 450 individuals in the US and has actually revealed collaborations with casinos in Iowa and New Jersey.

It works as danger supervisor for the Delaware Lottery and has actually invested millions along with a local designer in a New Jersey horse racing track.

Mr Asher said William Hill has ended up being a household name in Nevada but that's not always the goal all over.

"We certainly plan to have a really considerable brand existence in New Jersey," he stated. "In other states, it will just depend upon guideline and possibly who our regional partner is."

"The US is going to be the biggest sports betting market worldwide," he included. "Obviously that's not going to take place on the first day."